Fixture for fluorescent lamps



Dec. 19, 1950 L. LUDWIG FIXTURE F OR FLUORESCENT LAMPS 3 Sheets-Sheet 1 Filed Nov. 16, 1946 INVENTOR [cu/s [vow/q ATTORNEY Dec. 19, 1950 v L.. LUDWIG FIXTURE FOR FLUORESCENT LAMPS 3 Sheets-Sheet 2 Filed NOV. 16, 1946 p 5? s NS ow INVE NTOR [00/5 Zuarwq ATTORNEY Dec. 19, 1950 L. LUDWIG FIXTURE FOR FLUORESCENT LAMPS 5 Sheets-Sheet 3 Filed Nov. 16, 1946 HTTP NT H

each consisting of an elongated base 34 having lateral flanges 36, 38. The channels are so arranged that said flanges face each other and are disposed in close proximity and registration, thus causing the channels mutually to define an elongated space 39 of rectangular cross-section which is adapted to house the standard electrical elements of a fluorescent fixture, these elements comprising by way of example a ballast (coil or transformer) and wiring.

Both ends of the channels have outwardly extending hort integral legs til connected to the channels by curved portions L 2, said curved portions and legs in the main being of channelshaped cross-section and comprisin a base it and flanges 55. As is best seen in Figs. 2 and 7, the leg flanges t"? are somewhat shorter than the body flanges 3t, 38, this relative dimensioning being employed to facilitate bending the ends of the channels at the time the legs and curved pcrl tions 4d, d2 are formed. The tips 48 (Fig. 8) of the legs it are rounded as viewed from an end of the fixture and the flanges i6 terminate where the curvature resulting from said rounded formation begins.

Each leg has a larger circular opening 58 which, for the sake of appearance, may be concentric with the radius of curvature of the tip 48. The diameter of said opening is substantially in excess of the space between the contact pins of a fluorescent tube adapted to be used in the fixture it, this additional space being supplied, as will be apparent later on, to provide room for contact blades and insulation. A wide slot 52 leads from the opening to the outer edge of the tip of the leg 3!]. The portions of the base 44 of the leg in the region of said slot are reinforced by flanges 54 which define a depressed path of which the slot 52 is the open side.

The two mounting channels are fastened together by suitable means such as bolts 55 which clamp the bases 3 of said channels to each other and hold the ballast in place. The channels are secured to the closure plate 26 by nuts and bolts 56.

It will be appreciated that the ballast enclosure defined by the channels is open at both ends and that said channels ccnjointly form a squat H-shaped element, the ends of which are adapted to support a pair of fluorescent tubes about as long as the cross bar of the H. The open ends of the ballast enclosure are capped by end members 5t whose construction and arrangement are primary features of the present invention. Inasmuch as said end members are identical, only one will be described.

Said end members are molded in any suitable manner, e. g. transfer molding, from a plastic electrically non-conductive material which prefdeeper at the center of the end member (see Fig.

9) in order to cover the edges of the flanges 46 on said connecting portions 152 as they run into the body flanges 35, 38.

The base Wall 58 is essentially flat, and particularly so on its external surface 55, but said wall is provided with various apertures, ribs, bosses, ledges, platforms and wells for different purposes, such as to reinforce the end piece, to secure the end member to the fixture, to support the ends of fluorescent tubes, to support a starter, and to house contact blades which are adapted to engage the contact terminals of said tubes and starter.

Said base wall is provided with a plurality, e. g. four, bosses 68 (Figs. 5 and 10), each having a well 58 in registry with an aperture Ill in the leg bases 64. Drive screws 12 are inserted through the apertures l6 and forced into the wells 68 whereby to firmly hold the molded plastic end members to the elongated H-shaped metallic member.

The means integrally formed with the end members for holding the ends of fluorescent tubes in place and for supplying electric power thereto comprises a lamp socket housing including a low circular plateau M around whose periphery a circular ledge it is raised. Said led e is provided with two notches i8, 88 to admit lead wires t4 and with a pair of diametrically opposed notches 85, 8B which are employed to aid in properly positioning a lamp contact retainer plate 88 hereinafter more fully described, The ledge 76 also is provided with a wide slot 9|] approximately equal in width, at its entrance, to the width of the slot 52 in the leg 40. Said slot 98 has its edges defined by radially disposed stub ledges S2 extending from the ledge 76 toward the center of the plateau M.

Platforms 9e rise from the plateau adjacent the slots 55, 86, these platforms being slightly shorter than the ledge 76 so as to support the contact retainer plate 88 which is flush with the ledge 16. Another platform 96 runs diametrically across the plateau 14 toward the slot 90 terminating somewhat short thereof and forming a wall which divides into two equal parts the recess enclosed by the ledge it. The platform 96 is the same height as the platforms 94 and the tip 98 thereof is tapered toward the slot 70. The lateral edges of said platform 96 are provided with projections [til which cooperate with platforms I02 ex ending from the ledge 76 in the region of said projections to form pockets I84 which are adapted to aid in holding in place contact blades [96.

Said blades are formed from resilient electrically conductive strip stock, such for instance as Phosphor bronze, and each blade includes a lamp terminal engaging portion I08 and two bent end portions llfi, H2. The end portion H0 is designed to be received between a radial ledge 92 and the adjacent portion of the ledge 16, and the end portion H2 is designed to be received in the pocket 15 5.

When the contact blades are in position in the lamp socket housing, they are under slight compression, so that they will tend to remain in place. As indicated, a blade is disposed on each side of the wall 96. The lead Wires 82, 84 are secured to the contact blades in any suitable manner, as for instance by soldering.

Each of the platforms $4 is formed with a bore and the lamp contact retainer plate 88 has apertures registered with said bores to pass drive screws H adapted to be forced into the bores in order to hold the plate in place. The retainer plate is fabricated from electrical insulating material, as, for example, fiber impregnated with a thermosetting plastic. Said plate is received in the space enclosed by the ledges l6 and rests c eeses;

p oneme-platforms; Strand:theeledge nliithe laatenzheingofttheesameaheightaas saidimatforms: Thee-retainingplateshaswfonrzfingerssI I 6-; .I I 8; I I 22 umsertediinwtheiznotchesgilfi;.80-,-.18&and*85' respectively so: that:v the? plate; i rmly lockedagainst IOtB/biOIlg, Thesportion of; the plates ver the; s1ott90 isacutiawayasat I24 to provide an opening; towards which 1 two deep. divergent note-hes Iltcxtend; Saidnotches. run toboth sides of the-1 wall 96 -so.-.tha-t' the plate only 'par+ tie-11y covers the .-contact receivingrecesses. The notches I25; are spaced: apart at, their; bases slightly; in excess: ofithesdistance between :the two contact-terminals at the end of-"a conventional fluorescent. lama. The. contacteblades: I 06- ares-so formed that the terminal engagin portions I08 thereof; project, into the.-- space in back of the notches I26.-:adjacent thesbases of said notches, asbestseen in Fig; 3;

The-terminals .T" ofia alamp are introduced into the sockets; asfollowsz: Said terminals firstare guided. through a slot I 28 inthe flange (i2v aligned withtheslot 52inthe legsill. Said terminals next passthrough theslot 52 and. enterinto-the cutaway portion I24 of the retainer. plate. At thesame time the terminals pass through. the slot .88 in the ledge-I6. If. one .terminalis lead.-

ing; the other,v it..wil1 either; strike thetip. 933 of the-- wall 950 and be diverted to. the recess on or the-other side of the said wall, or, said terminal will. already be -sooriented: that it will; enter a recessrto one sideof the wall Without turningthe lamp. In eithercase, the otherterminal .will enter the: recess-r011. the othersideofthe wall 96, the terminals at such.v time each extending through a. different oneofr the: notches I26; When the terminals-reach thebases ofythenotches, they will press against: theseng eing portions I08 of the contact-blades; Saidihortions each havezaslight outward": bend therein pointing away from the wall. 96 so: that, once-the terminals are: in: said hendsthey will: be held there; against accidental displacement and. will'makegood electricalcngagement: with: the: contact, blades.

' It may be' mentioned-here; that thepartioular form of socket zjust: described canzbeconsiderae bly modified without:departing from the spirit offthis phase of mysinvention'.whichibasically. resides in forming the socketuhousingfintegral with the end'member'58; Moreover, said housing pref-- erably is sofashioned thatrthe-base thereof (the portion remote from. the fluorescent: tube) is. an integral part of the socket; while the-portion of the=socket closest to the-fluorescent-tuberisa separrate element (the lamp contact" retainer platemember,- for holding a starter in place and sup I plying electric power-thereto comprisesa: starter.

socket-housing including; a deep well" I30 open:-

ing" at the external surface 65 of the end mem ber; S'aid" well isclosed: at itsbottom: end 'by a:

panel I32 in which a pair of'concentric. arcuate keyhole slots I34 are formed; Thesideof the panel facing the fluorescent: tubes hastwo re cesses- I35 therein, the same beingseparated by. a wal'l I36. Said;- recessesincludespaced notches I38 -which receive-the ends-or contact-blades I4 These-blades are-so shaped-thatwhen their ends- Fri) 61': arezdisoosed i ll l 'lfiifii lffi fiidi reces es;- aeportiou M oi; ach blade: will b e =.expo,sed throu hi the smaller en of a keyhole. slot; 34.. Thisgp t on wires:- connect the starter socket; contact blades.

andlamp socket contact;,blades I061-ina convene tional electricalcircuit, such aspisgwell known in.

the art.

Therecesses: l35pand contact blades; Ill). are

covered by a starter: con act. retainer plate; I48

restingon thesides of said recesses; Said-plate hastwo indentations I50, in its periphery which are. fitted on bossesI filraised on the ledgeswhich define the recesses I34, whereby to prevent'rela tive rotation of the plate I48 andthe endmember, 58... Saidplate I48 is held in position by a. 1 pair of drive screws I54 passing through openingsin the plate and forced intobores inthe wall I36. It will be observed that, with the foregoing, arrangement, both the starter socket housing and the lamp socket housings are integrally formed with each end member and that. the.

starter socket faces in a direction opposite. to. that in which the lamp sockets face so thatthe starter is readily accessible for, removement and replacement. The starter well may be made deep enough to conceal most of the starter can so that only the top thereof'vvill be visible.

The power for-thefluorescent lamps is derived from an electric light socket I56 disposed within the canopy I5. This socket receives a screw plug Hiew-hiclrmay be ofthe two-part detachable type including a cap with projecting blades Said" plug is connected to the ballast by a pair-of lead-wires I60.

Desirably; various-portions of the-end member may be' reinforced toguard against breakage; Thus; thewell I38 can be reinforcedby longitudinal ribs E62 and transverse ribs I64; these. ribs-also helping to'strengthen the base 60.

Despite the complex-configuration of theconcealedsurface of the end member, the external surface of its base isentirely flat with the exception ofthe well I36, thus imparting a clean andpl'easing appearance to saidmember.

It'willthus beseen thatthere is provided a fluorescent electric fixture which achieves the several objects of the invention and is well adapted to meet the conditions of practical use.

As various possib e embodiments might be made of the above invention, and, as various changes mightbe made in the embodiment above set' forth, it is to be understoodthat all matter herein described or, shown in the accompanying drawings is to be interpreted illustrative andinot in a; limiting sense.

Having thus described the inventionthere is claimed as new and desired to be secured. by,

Letters Patent:

1. A fluorescent electric fixture comnrising a pair of elongated' sheet metal channels, means to secure said channels with the tips. ofjthechannel flanges in registration and proximity and facing one" another, and with the channel bases remote; whereby to form a hollow open I h endedmember; both ends of-both said channels being outturnedapairof molded plastic members one on each end of said pair of' channels and closing the open ends thereof, means to connect each molded member directly to said pair of channels, each of said plastic members having integrally molded therewith at least one socketadapted to detachably support an end of an elongated fluorescent electric lamp, said socket extending through an opening in the outturned end of the associated channel and at least one of the plastic members having integrally molded therewith a socket for detachably supporting a starter.

2. A fluorescent electric fixture comprising a pair of elongated sheet metal channels, means to secure said channels with the tips of the channel flanges in registration and proximity and facing one another, and with the channel bases remote, whereby to form a hollow openended member, both ends of both said channels having outturned registered metallic flanges, a

pair of molded plastic members one on each end of said pair of channels and closing the open ends thereof, said plastic members covering the outer surfaces of the flanges and leaving exposed the surfaces of said flanges which face each other, means to connect said molded members directly to said flanges, each of said plastic members having at least one socket adapted to detachably support an end of an elongated fluorescent electric lamp, and at least one of the plastic members having a socket for detachably supporting a starter,

3. A fluorescent electric fixture as set forth in claim 2 wherein each plastic member and its associated flange defines an enclosed space to house the socket contacts, said plastic member constituting all of the outer sides except one of said space.

4. A two-lamp fluorescent electric fixture comprisinga pair of elongated sheet metal channels, means to secure said channels to each other with the tips of the channel flanges in registration and proximity and facing one another, and with the channel bases remote, whereby to form a hollow open-ended enclosure adapted to receive electric equipment for the fixture, both ends of both said channels being outturned whereby to define a squat H-shaped member which is adapted to have an elongated fluorescent lamp disposed on each side of the cross bar thereof and parallel to said cross bar, a fluorescent lamp socket disposed on each outturned channel end, the sockets on the same sides of the cross bar being in registration, a 7

starter socket at each end of the H-shaped memher and facing in a direction parallel to and away from the cross bar and molded plastic end members to close both ends of the enclosure and the outturned channel ends, said end members having peripheral flanges which overlie flanges of the outturned channel ends.

H 5, A two-lamp fluorescent electric fixture comprising a pair of elongated sheet metal channels, means to secure said channels to each other with the tips of the channel flanges in registration and proximity and facing one another, and with the channel bases remote, whereby to form a hollow open-ended enclosure adapted to receive electric equipment for the fixture, both ends of both said channels being outturned whereby to define a squat H-shaped member which is adapted to have an elongated fluo rescent lamp disposed on each side of the cross bar thereof and parallel to said cross bar, a

molded plastic member mounted on each end of the fixture and closing the ends of the hollow enclosure and the outturned channel ends, each of said outturned channel ends having an opening therein, each of said end members having a pair of lamp sockets, the housing whereof is molded in one piece with the end member and is disposed in registry with the openings inthe outturned channel ends, said housings having recesses therein opening toward the center of the fixture, contact bladesin said recesses, retaining plates partially covering said recesses, and a starter socket in each of said end members, the housing whereof is molded integrally with said member and has contact blades secured therein.

6. A two-lamp fluorescent electric fixture comprising a pair of elongated sheet metal channels, means to secure said channels to each other with the tips of the channel flanges in registration and proximity and facing one another, and with the channel bases remote, wher by to form a hollow openended enclosure adapted to receive electric equipment for the fixture, both ends of both said channels being outturned whereby to define a squat H-shaped member which is adapted to have an elongated fluorescent lamp disposed on each side of the cross bar thereof and parallel to said cross bar, a molded plastic member mounted on each end of the fixture and closing the ends of the hollow enclosure and the outturned channel ends, each of said outturned channel ends having an opening therein, each of said end members having a pair of lamp sock ets, the housing whereof is molded in one piece with the end member and is disposed in registry with the openings in the outturned channel ends, said housings having recesses therein opening toward the center of the fixture, contact blades in said recesses, retaining plates partially covering said recesses, and a starter socket in each of said end members, the housing whereof is molded integrally with said member and has contact blades secured therein, said starter socket facing outwardly and being disposed at the bottom of a deep well whereby a starter received therein is substantially concealed.

'7. A two-lamp fluorescent electric fixture comprising a pair of elongated sheet metal channels, means to secure said channels to each other with the tips of the channel flanges in registration and proximity and facing one another, and with the channel bases remote, whereby to form a hollow open-ended enclosure adapted to receive electric equipment for the fixture, both ends of both said channels being outturned whereby to define a squat H-shaped member which is adapted to have an elongated fluorescent lamp disposed on each side of the cross bar thereof and parallel to said cross 0 a molded plastic member mounted on each ei d of the fixture and closing the ends of the hollow enclosure and the outturned channel ends, each of said outturned channel ends having an opening therein, each of said end members having a pair of lamp sockets; the housing whereof is molded in one piece with the end mer her and is disposed in registry with the openings in the outturned channel ends, said housings having recesses therein opening toward the center of the fixture, contact blades in said recesses, retaining plates'partially covering said recess, and a starter socket in each of said end members, the housing whereof is molded integrally with said member and has contact blades secured therein, said 9 starter socket facing outwardly and being disposed at the bottom of a deep Well whereby a starter received therein is substantially concealed, said end members having peripheral flanges which overlie the flanges of the outturned channel ends.

LOUIS LUDWIG.

REFERENGES CITED The following references are of record in the 19 file of this patent:

Number UNITED STATES PATENTS Name Date House May 27, 1941 Curtis July 7, 1942 Curtis July 7, 1942 Schelgunov Feb. 23, 1943 Whittaker Mar. 21, 1944 Ainsworth Apr. 18, 1944 Kruger -1 Aug. 3,,1948 Kulka, Sept. 14, 1948 

